Floating mine



M. L. ILFELD FLOATING MINE Oct 26, 1948.

2 Sheets-Sheet 1 Filed July 1.4, 1944 Oct. 26, 1948. I lLFELD 2,452,053

' FLOATING MINE I Filed July 14, 1944 2 Sheets-Sheet 2 Patented Oct. 26, 1948 UNI TED STA'l ES PATENT OFF-ICE 2,452,055"

FLOATING MINE Max L. ntdmnmma States Army Application Julyld, 1944, Serial No. 544,967

(Granted under the act of March 3, 1883, as amended April '30, 1928; 370 0. G. 757) .5 -.Claims.

The "invention described herein may be manufactored and used by or for the Government for governmental purposes, without payment to me of any royalty thereon.

This invention relates -to a new type of floating bangalore mine which is actuated by contact.

The object of this invention is to provide a mine which, 'uponcontaot'with boats or men, will detonate and destroy them.

A 'further object of this invention is to provide amine simple in construction and mechanically operable so that long periods of inactivity-will not affect-its operation.

A still further object of this invention is to provide a floating 'bangalore mine with numerous safety devices so that there is no possibility of an explosion before the various safety devices have been removed.

A further object of this invention :is to use a water soluble or dissolva'ble substance as a temporary safety device.

With the above and other objects and advantages in View, the invention consists of certain features of construction andoperation of parts which will hereinafter be described and shown in the accompanying drawings, in which:

Figure l'is an exploded view of the mine showing the casing, complete firing mechanism and bangalore torpedo;

Figure 2 is a view of the complete firing mechanism and bangalore torpedo in assembled condition ready to be inserted in the casing;

Figure 3 is an enlarged detailed view of the firingmechanism proper;

Figure 4isan enlarged viewpf the firing mechanism and bangalore =torpedo positioned in the casing in operative position with safety pins l9 and 20 pulled out;

Figure 5 is a cross sectional view of the mine taken onthe line 55 of Figure 4;

Figure 6 is a cross sectional view of the mine taken on the line 66 of Figure 4; and

Figure 7'is an enlargedview of the end closure or cover structure. 7

Referrirg more specifically to the; drawings;

. Casing I is the housing for the firing .m chanism and bangalore torpedo. This casing may be made of'thin gauge galvanized-iron, plastic ma te riaL-paraffin paper or anyother water-proof and preferably light weight material. -2 and 13 indicate the anchor lugs by which the floating mine may be anchored in operative condition in the water at any location.

The cover indicated by numeral 4 has handles 5 and well 6 to hold the dissolvable material 1. Covering the Well 6 is a cap 8 having a perforation 9 therein. The inner end of the well .6 is closed by a thin, preferably metal, diaphragm .19. The diaphragm I0 isof such construction thatit will prevent water in well 6, which has entered through perforation 9, from entering the casing I thereby making the casing airtight and buoyant. However, any pressure against this diaphragm by pin 36 will besufiicient to rupture it.

Cover 4 also compriscsa bolt H and thumb screw IZ. As the thumb screw is turned. .down upon the handles 5 their outer ends .are forced into the recess in the end of .the casing, whereby a .wedging action willresult making the container water-proof.

The conventional .bangalore torpedo'or hangalore is indicated atv l3. .14 indicates the rear clip member .of the firing mechanism which has a circular. base adapted to receive the rear endof the bangalore and vertical sides having an arch at their upper end to fit snugly inside the-casing. A partition member .or support 15 in the center of this rear clip has a notch .in its upper end to receive the enlarged head of the ceramic rod I 6. This rod may be of glass. plastic or other breakable material. The strength of the rod, i. .e., its

thickness and material of which it ismade, will:

determine the amount of shock necessary -to.set off the mine.

The firing mechanism proper comprises .a lower circular extension 11 adapted to en age the front end of the bangalore and having a reenforced hole therein adapted to receive the firing pin H3. The firing pin I8 has a vertical safety pin vHiand a "horizontal safety pin therethrough which prevent the .firing pin from igniting the hangalore. Also safety pin '20 secures safety pin .22 in place. Cord String or wire 2| is attached to these pins so that they maybe withdrawn at the appropriate time. In addition to these two safety pins there is an additional safety pin 22 the op: eration of which will be explained subsequently. Above and secured to the circular extension. I1 is a base plate 23 having an upturn at one end andian arched extension 24 integral with onsecured thereto 'bywe'lding or some other means at the other end. Extending from the upwardly extending portion of the base plate is a projection 25 which, together with projection 35, servesto guide'the spring 26. Located on and slidab le with respect to base plate 2?: is movable element 27 comprised of rear member 28 and forward member 29. The rear member has at its upper end a notch 30-to receive the ceramic rod IS. The forward member 29 has secured to it an upper guide 3| and a lower guide 32 in order to guide a. pin

33 which is adapted to engage loop 34 on firing pin 18. Also positioned on the forward member is a bolt 36 which at the appropriate time is adapted to break diaphragm l0.

The operation of this device against ships, personnel and military equipment is as follows: The casing I has inserted in it the bangalore l3 and firing mechanism complete after which the cover 4 is put on and securely locked by thumb screw 12 forcing the handles 5 to engage in the recessed lip of the container. The mine may be stored in this way indefinitely in the zone of the interior or theater of operations.

When it is contemplated to use the mine, the cover is taken off and safety pins l9 and are withdrawn from the firing pin by means of the strings 2|. However, the mine may still besubjected to rough handling or transportation if it is carried in an upright. position because safety pin 22 is still in place. This safety pin is disengaged by turning the mine upside down so that the pin will fall out. Obviously, this isnot done until the mine is ready to be used.

A pellet of dissolvable material, such as a salt tablet preferably, may be carried in the well 6 of the cover or may be inserted just prior to use.

The mine is then dropped into the water which has been determined to be mined. Even if the ceramic rod is broken at this time, the mine is still safe because the dissolvable material which forms the backing for the diaphragm l0 would prevent the movable element 21 from going forward. However, the water immediately starts to act on the salt tablet. Normally, the pellet should be good for approximately three hours, but, any period of time may be obtained by using pellets of different composition and crystallization. After the pellet has dissolved the mine is armed, since salt pellet 9 no longer forms a backing for thin diaphragm l I]. There would be no resistance to pin 36 puncturing the diaphragm and allowing movable element 21 to go forward when the rod I6 is broken. A shock or jar will break the ceramic rod and, if the salt tablet has dissolved, allow the spring 26 to push the movable element 2! forward carrying with it guides 3I,'32 and pin 33. The pin 33 engaging the firing pin loop 34 actuates the firing pin l8 thereby detonating the explosive charge.

As can be ascertained by the abovedisclosure and drawings, I have provided a new and novel explosive assembly having three eparate and distinct safety devices for use in different and distinct stages of its movement from storage to use. Although, the invention has been illustrated as a floating mine, I do not desire to limit my device to this use. The dissolvable element may be dispensed with and the mine is adaptable for use as an airplane bomb, a land mine, a mortar grenade or a hand grenade. The type of fuse inserted in the detonating charge would determine whether the mine were point contact or a time delay fuse of various periods of time. 1

Having thus described my invention, what .I claim as new and wish to secure by Letters Patent is:

1. In an explosive device, a casing, an explosive charge, a firing mechanism, said firing mechanism comprising a firing pin, a spring adapted to move said, firing pin, and a frangible element adapted to hold said spring in operative position,

and safety means adapted to hold the spring to prevent the untimely detonation of the charge in the event the frangible element is broken, the safety means comprising a well, a dissolvable element therein, a, perforated cap on one end of the well so that water may enter the well and dissolve the dissolvable element, a frangible cap on the other end of the well, and means engaging the frangible cap and the spring to prevent movement of the spring until the dissolvable element is dissolved.

2. In an explosive device, means to actuate the firing pin, comprising a clip for each end of the explosive charge, upwardly extending projections on said clips, a movable element on one of said projections, said movable element connected to 'the firing pin, a spring to actuate said movable element, a frangible element positioned to hold said movable element in operative position so that when the frangible element is broken the movable element will be forced to move the spring thereby causing the firing pin to move and the explosive charge to detonate.

3. In an explosive device, a buoyant casing-an explosive charge therein, a cover for said casing, a frangible element formed in said cover, spring actuated means for puncturing said frangible element to detonate said charge, a soluble substance positioned in said cover and opposed to said spring actuated means, said soluble substance adapted to release said springactuated means upon being dissolved, and a perforated capfor retaining said substance in position.

4. In an explosive device, a buoyant casing, an explosive charge therein, a cover for said casing, spring actuated means to detonate said charge, a well in said cover adapted to hold a dissolvable substance opposed to the action of said spring actuated means, a perforated cap forsaid well adapted to provide access to said dissolvable substance, and a frangible diaphragm adapted to be punctured by said spring actuated means when said dissolvable substance is dissolved.

5. In an explosive device, a casing; an explosive charge therein, a firing mechanism, said firing mechanism comprising a firing pin, and a spring adapted to move said firing pin, a frangible rod spaced from and positioned parallel to said firing pin and adapted to hold said spring in a nonfiring position; and an extensively perforated well on the said casing, a dissolvable substance positioned in the well, and means engaging the said substance and the spring, whereby the substance, when undissolved, prevents the spring from actuating the firing pin.

MAX L. ILFELD.

REFERENCES CITED The following references are of record inthe file of this patent:

UNITED STATES PATENTS Number Name Date 1,243,974 Powers et' al. Oct. 23, 1917 FOREIGN PATENTS Number Country Date 6,545 Great Britain 1914 6,973 Great Britain 1915 263,985 Italy Apr. 10, i929 

